Kratos Defense & Security Solutions (KTOS) 10-K 2007 FY Annual report

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EXHIBIT 32.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER
PURSUANT TO SECTION 18 U.S.C SECTION 1350
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Annual Report of Kratos Defense & Security Solutions, Inc. (the "Company") on Form 10-K for the fiscal year ended December 31, 2007 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Eric M. DeMarco, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

        1.     The Report fully complies with the requirements of Section 13(a) or 15(d), of the Securities Exchange Act of 1934; and

        2.     That the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: March 27, 2008

KRATOS DEFENSE & SECURITY SOLUTIONS, INC.

/s/  ERIC M. DEMARCO      Chief Executive Officer

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EXHIBIT 32.1